What happens when you have Ivan Nova in the fourth spot and Freddy Garcia behind the neophyte, instead of Cliff Lee second and Andy Pettitte third?

You answer to “Underdog.”

Never mind that the Yankees have three Hall of Fame locks, two with solid chances and another on the fringe of entry into Cooperstown.

Ignore the Steinbrenner family’s vault that gets hit annually for $200 million-plus in salaries. Disregard the cash cow dressed as the YES network. And turn your head about Yankee Stadium, a venue that inhales more money than Las Vegas on Super Bowl weekend.

And then focus on the hardest-to-believe fact of the 2011 season that commences today when the Yankees host the Tigers: The 27-time World Series champions playing the role of Rocky, Villanova, Buster Douglas and Hickory High.

“It sounds strange because of our talent level and the past that nobody is picking us,” Opening Day starter CC Sabathia said yesterday. “It’s kind of funny, we won 95 games last year.”

Sabathia understands why the improved Red Sox are the sexy pick to win the AL East. That doesn’t mean, however, the Yankees have conceded the crown to their blood rival. In fact, Sabathia talked about a ride up the Canyon of Heroes in November.

Asked if he was picking the underdog Yankees to win the East or it all, Sabathia didn’t flinch.

“That’s to win the whole thing. I wouldn’t show up if I didn’t believe that,” said Sabathia, who will make his third Opening Day start in three seasons with the Yankees.

“The Red Sox got better,” Sabathia said. “They had a lot of injuries last year. We just have to wait to see how it plays out on the field.”

The Las Vegas Hilton has the Red Sox listed at 10-17 to win the East, the Yankees 2-1. For the World Series, the Phillies are 5-2, Red Sox 4-1 and Yankees 6-1.

If the Yankees feed off being the underdog, manager Joe Girardi isn’t going to attempt to change that.

And Mariano Rivera, who with Derek Jeter and Alex Rodriguez is a Hall of Fame lock, dismissed the talk of being a second-class citizen.

“We don’t care about Boston. We cannot control what they do,” Rivera said. “We have a great team. Whatever people say doesn’t mean anything.”

Across 16 seasons, Jeter’s club hasn’t been cast in the underdog role often. It happened last year in the ALDS when the Twins were a slight favorite — and got swept by the Bombers.

“We have gone into the season favored. It really doesn’t make a difference,” said Jeter, who starts the season 74 hits away from 3,000. “Every season, the goal is to win a championship.”

It’s one thing to have a goal and another to taste reality. And the reality going into this year is there are a lot of serious questions that can’t be made up, because there is a chip on the Yankees’ shoulders about the Red Sox being the favorite.

“It’s different, it’s not something you hear very often,” Girardi said of the Yankees being the underdog.

“I can’t remember the last time I heard those words used. I have been here since ’96 [starting as a player], and I don’t remember a year when you hear about the Yankees being underdogs. I don’t know if we are going to sneak up on anyone.”

The Yankees sneak up on nobody. It’s just this year they don’t start the race in the pole position.